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Cast of an Oldowan chopper

Chopper tool from Oldowan or Mode 1 technology. It is uncertain who the makers of these stone tools were. The tool makers may have been early populations of Homo habilis or they may have been made by another species.
This artefact is a round, worn stone from which flakes have been removed on one side, ie it is unifacial. These tools were used for chopping or were left over after stone flakes have been taken off for other purposes.